1. Field of the Invention
The present invention relates to a mass spectrometer, a method of mass spectrometry and a method of manufacturing an ion guide for a mass spectrometer.
2. Discussion of the Prior Art
Multipole rod set RF ion guides are known and are used for transporting ions at relatively low pressures (e.g. <10−4 mbar) where ion collisions with background gas molecules are unlikely and also for transporting ions at intermediate pressures (e.g. 10−4-10 mbar) where ion-molecule collisions may be expected to occur. Multipole rod set RF ion guides are used at intermediate pressures for a wide range of applications. For example, multipole rod set RF ion guides are used as collision cells where ion-molecule collisions are intended to induce ion fragmentation and as reaction cells where ion-molecule collisions are intended to result in ion-molecule reactions. Multipole rod set RF ion guides are also used as cooling devices where ion-molecule collisions lead to equilibration of the ion and gas molecule temperatures or kinetic energies. Known multipole rod set RF ion guides have a straight central axis with a single ion entrance and a single ion exit.
It is desired to provide a mass spectrometer having an improved RF ion guide.